New installed Gitea working - but how to crate the fist file for code

i Installed gitea on debian 10 without problem!

createt a user
createt a repository

but how to create a first file with code, in this repository?

if i mirror a github content there is a option to add a new file.
But not when crating something new

would be happy for a small hint where to find it.

have a nice day